1. Field of the Invention
The present invention relates to tool batteries, and in particular to tool batteries that can be connected to tool bodies of electric tools.
2. Description of the Related Art
A known tool battery has a book for locking against a tool body of an electric tool when the tool battery is moved to slide along the tool body in a given direction. In this connection, a battery housing of the battery has an opening, through which a lock claw of the book can protrude to the outside of the battery housing. The battery housing has another opening, where an operation member for releasing the lock condition caused by the hook is exposed to the outside.
This type of tool batter is disclosed, for example, in Japanese Laid-Open Patent Publication No. 2001-229895. FIGS. 10(A) and 10(B) show a tool battery disclosed in this publication. Referring to FIGS. 10(A) and 10(B), a tool battery 100 can be connected to a tool body 110 of an electric power tool by moving the tool battery 100 along the tool body 110 in the state that a front end (right end as viewed in FIG. 10(B)) of a slide rail 102 of the tool battery 100 is engaged with a battery connecting portion 112 of the tool body 110. A hook 105 is positioned at the left end of the battery housing 101 and can lock the tool battery 100 against the tool body 110 not to slide relative thereto when the tool battery 100 and the tool body 110 have been connected to each other. The hook 105 has a lock claw 105r and an operation portion 105x and is normally biased upward by a coil spring 106. The lock claw 105r can protrude upwardly from an opening 101h formed in the upper surface of the battery housing 101. The operation portion 105x is operable for releasing a lock condition achieved by the lock claw 105r and is exposed at an opening 101y formed in the left side surface of the battery housing 101.
Therefore, when the tool battery 100 is slide relative to the tool body 110 to reach the right and position as shown in FIG. 10(B), the lock claw 105r of the hook 105 protrudes upward from the opening 101h of the battery housing 101 by the force of the coil spring 106 and engages a lock wall surface formed on the tool body 110. Therefore, the tool battery 100 is locked against the tool body 110 not to slide relative thereto.
When the user presses the operation portion 105 of the hook 105, which is exposed at the opening 101y of the battery housing 101, against the force of the coil spring 106, the lock claw 105r moves not to protrude from the opening 101h, so that the lock condition of the tool battery 100 is released.
As described above, in the battery housing 101 of the tool battery 100, there are provided the opening 101h, through which the lock claw 105r of the hook 105 can protrude upward, and the opening 101y for enabling the operation of the operation portion 105x of the hook 105 for releasing the lock condition. Therefore, in the even that the tool battery 100 gets wet with rain, etc., it may be possible that water enters the battery housing 101 from the openings 101h and 101y. Because there is no partition between a space where the hook 105 is stored and a space where battery cells (not shown) are stored, water entering the battery housing 101 may reach the battery cells. If this occurs, the battery cells may be short-circuited to cause failure of the tool battery 100.
Therefore, there is a need in the art for a tool battery that may not cause a substantial problem even in the event that the tool battery gets wet.